| 摘要 |
A nonvolatile semiconductor memory device includes: a matrix of nonvolatile memory cells (301) formed at intersections of word lines (302) and bit lines (303), each memory cell being connected between a first power supply line (GND) of the device and the bit line (303) at its intersection; and sense amplifiers (340) corresponding to the bit lines (303). At least one sense amplifier (340) comprises: a sensing node (320) connected operatively, via such a corresponding bit line (303), to one of the memory cells (301); current detection means (308, 312, 317-319), having a current path between the sensing node (320) and a second power supply line (306) (Vcc) of the device, and operable to detect when the current flowing through the current path exceeds a predetermined value; and current supplementing means (314, 315), connected operatively between the sensing node (320) and the first power supply line, for causing a supplementary current, additional to a memory cell current caused to flow by the memory cell (301) when turned on, to flow through the current path. The current supplementing means (314, 315) are operable to increase the value of the supplementary current in response to a change in the sensing-node potential towards the first-power-supply-line potential. A memory device including such a sense amplifier (340) is able to achieve a higher data reading speed. <IMAGE> |
